High temperature/porcelain terra sigillata

[Valeria]

I am wondering how to fire - in an electric kiln- burnished pots brushed with a porcelain/stoneware terra sigillata- or even just burnished! Is this possible? 

 What temperature would you suggest to fire to? 
I’d like for them to be strong enough to be carried at markets and slightly shiny and smooth on the outside. 

Any knowledgeable advice and tips would be valued. Thank you 

V. 

 

[Min]

4 hours ago, Valeria said:

I am wondering how to fire - in an electric kiln- burnished pots brushed with a porcelain/stoneware terra sigillata- or even just burnished! Is this possible? 

Yes

4 hours ago, Valeria said:

What temperature would you suggest to fire to? 

For burnished with no terra sig then I wouldn't go above cone 016 which is approx 770C if you fire at 60C an hour for the last 100C of the firing.

For terra sig you can go hotter without loosing the sheen, up to cone 04 should be okay. (1060C approx, going at the same rate of 60C for the last 100C)

4 hours ago, Valeria said:

I’d like for them to be strong enough to be carried at markets

Not sure on your meaning here.

Welcome to the forum.

[Magnolia Mud Research]

I use terra sigs on the bottoms of cone 10 fired clay bodies for decorative surfaces the need a smooth slight shine without glaze, and for smooth burnished foot rings.  Yes the surface is different than being fired to Raku (and lower) temperatures; the polished effect does remain smooth and polished.  This approach has worked beautifully at cone 3 oxidation, cone 5 oxy & reduction, cone 10 reduction, and  cone 5 through 11 wood firing.  

Try it!  evaluate the outcome, then decide if you want to continue using the technique.     

LT